[Expression of CD4+ CD25+ regulatory T cells in peripheral blood and salivary gland of patients with primary Sjögren's syndrome].
ABSTRACT To investigate the expression of CD(4)(+) CD(25)(+) regulatory T cells (Tregs) in the peripheral blood and salivary gland of patients with primary Sjögren's syndrome (pSS).
Samples of peripheral venous blood were collected from 57 newly diagnosed pSS patients, 1 male and 56 females, aged 47 (20 approximately 76), and 46 healthy controls. The levels of CD(4)(+) CD(25)(+) T regulatory cells and CD(4)(+) CD(25)(high) T regulatory cells in the peripheral blood were measured by flow-cytometric assay. Biopsy specimens of labial gland were collected from the 57 patients and 6 healthy person or patients with labial gland cyst. Pathological examination was conducted by light microscopy. Immunohistochemistry was conducted, by using monoclonal mouse anti-human to detect the expression of CD25, CD4, CD8, and CD68. Western blotting was used to detect the levels of IgG, IgM, and IgA. The salivary flow rate was measured. Schirmer's test was used to measure the tear flow rate.
The level of CD(4)(+) CD(25)(+) Tregs in the blood of pSS patients was 6.9% (2.84% - 13.50%), significantly lower than that of the healthy controls [10.9% (5.77% - 15.3%), P < 0.001). The level of CD(4)(+) CD(25)(high) Tregs the blood of pSS patients was 0.6% (0.001% - 1.83%), significantly lower than that of the healthy controls [1.1% (0.13% - 2.45%), P < 0.001]. Immunohistochemistry showed that most of the infiltrating lymphocytes in the labial gland of the pSS patients were CD(4)(+) T cells, and there was no CD(25)(+) T cell in both groups. The numbers of peripheral CD(4)(+) CD(25)(+) T cells and CD(4)(+) CD(25)(high) Tregs in the pSS patients were not correlated with the tear flow rate, salivary flow rate, anti-SS-A/SS-B antibodies, and immunoglobulin level.
The pSS patients show an absence of CD(4)(+) CD(25)(+) T cell in the labial gland of pSS patients, and reduction of the numbers of CD(4)(+) CD(25)(+) and CD(4)(+) CD(25)(high) Tregs in the peripheral blood, which suggests that Tregs play an important role in the pathogenesis of salivary gland destruction in SS.
- SourceAvailable from: Gabor Papp[Show abstract] [Hide abstract]
ABSTRACT: The aim of the present study was to describe subsets of cells with regulatory properties in primary Sjögren's syndrome (pSS), and to correlate these cell populations with clinical symptoms. Among the 32 investigated patients, 23 had extraglandular manifestations (EGMs), while nine had only glandular symptoms. Twenty healthy individuals served as controls. The percentages of natural killer (NK), natural killer T cells (NK T), interleukin (IL)-10 producing T regulatory type 1 (Tr1) cells and CD4(+)CD25(+) regulatory T cells (T(reg)) cells were determined by flow cytometry and serum cytokine levels of IL-4, IL-6, IL-10, tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma were evaluated by enzyme-linked immunosorbent assay (ELISA). Functional tests were carried out to assess the suppressor properties of T(reg) cells in patients and controls. Peripheral NK, NK T and Tr1 cell percentages were elevated in pSS, while CD4(+)CD25(+) T(reg) cells showed reduced frequencies in patients compared to controls. In pSS, elevated percentages of NK T, Tr1 and CD4(+)CD25(+) T(reg) cells were observed in patients with EGMs, when compared to patients with sicca symptoms only. CD4(+)CD25(+) T(reg) cell percentages showed a negative correlation with sialometry values. The in vitro functional assay demonstrated lower suppression activity of CD4(+)CD25(+) T(reg) cells in patients compared to controls. Serum IL-6 and TNF-alpha levels were elevated, while IL-10 was decreased in patients compared to controls. Negative correlation was found between IL-10 levels and the percentages of Tr1 cells. Changes in the investigated subsets of regulatory cells in pSS may contribute to the development and progression of the disease.Clinical & Experimental Immunology 10/2009; 157(3):343-9. DOI:10.1111/j.1365-2249.2009.03966.x · 3.28 Impact Factor